Name=!player filter criteria for command blocks does not work

ran a command block to test for players other than me within a particular radius, expecting it to not react to my player
(/testfor @p[Name=!ComatoseChimera,r=10])

it activated the comparetor when i got close

steps to reproduce
1. place a command clock
2. put in this command
3. /testfor @p[Name=!ComatoseChimera,r=10] (replace player name with your own)
4. apply a clock input
5. apply a comparator output
6. walk back and forth past the 10 block border